.top-pillar, .bottom-pillar{
    background: greenyellow;
    width: 100%;
    position: absolute;
}
.top-pillar{
    top: 0;
    border-top: darkgreen solid 2px;
}
.bottom-pillar{
    bottom: 0;
    border-bottom: darkgreen solid 2px;
}
.pillar-container{
    position: absolute;
    width: 4%;
    height: 100%;
}
.active-pillar{
    background: orange
}